Search results for: natural boundary condition

Authors: Akhilesh Mishra, Geeta Rai, Arvind Srivastava, Nalini Tiwari

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A field experiment was conducted during two consecutive Rabi seasons of 2007 and 2008 to study the economics of different bio-fertilizer’s inoculations in fieldpea (cv. Jai) at Chandra Shekhar Azad University of Agriculture and Technology, Kanpur (India). Results indicated that the seed inoculation with Rhizobium + PSB + PGPR improved all the growth; yield attributes and yields of field pea. Fresh and dry weight plant-1, nodules number and dry weight plant-1 were found significantly maximum. Number of grains pod-1, number and weight of pods plant-1 at maturity attributed significantly in increasing the grain yield as well as net return. On pooled basis, maximum net income (Rs.22169 ha-1) was obtained with the use of Rhizobium + PSB + PGPR which was improved by a margin of Rs.1502 (6.77%), 2972 (13.40%), 2672 (12.05%), 5212 (23.51%), 6176 (27.85%), 4666 (21.04%) and 8842/ha (39.88%) over the inoculation of PSB + PGPR, Rhizobium + PGPR, Rhizobium + PSB, PGPR, PSB, Rhizobium and control, respectively. Thus, it can be recommended that to earn the maximum net profit from dwarf field pea, seed should be inoculated with Rhizobium + PSB + PGPR.

Keywords: rhizobium, phosphorus solubilizing bacteria, plant growth promoting rhizobacteria, field pea

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Authors: Mohieddine Benghersallah, Mohamed Zakaria Zahaf, Ali Medjber, Idriss Tibakh

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The objective of this study is to analyse the effects of cutting parameters on surface roughness in dry face milling using statistical techniques. We studied the effect of the microstructure of AISI 52100 steel on machinability before and after hardening. The machining tests were carried out on a high rigidity vertical milling machine with a 25 mm diameter face milling cutter equipped with micro-grain bicarbide inserts with PVD (Ti, AlN) coating in GC1030 grade. A Taguchi L9 experiment plan is adopted. Analysis of variance (ANOVA) was used to determine the effects of cutting parameters (Vc, fz, ap) on the roughness (Ra) of the machined surface. Regression analysis to assess the machinability of steel presented mathematical models of roughness and the combination of parameters to minimize it. The recorded results show that feed per tooth has the most significant effect on the surface condition for both steel treatment conditions. The best roughnesses were obtained for the hardened AISI 52100 steel.

Keywords: machinability, heat treatment, microstructure, surface roughness, Taguchi method

Procedia PDF Downloads 133

Authors: A. Mahshid Kakouei, B. Kumaran Suberamanin, C. Sabzali Musa Kahn, D. Mina Kakouei

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This study aims to identify suitable conservative product for the conservation and restoration of historical Zelkova Carpinifolia wood located in humid weather. The superficial properties and hardness of 14 compounds treated with several consolidants were compared. The consolidants have been applied alone, with synthetic resin or with protein glues and natural resins by the brushing method. Colorimetric measurements, observation methods and hardness tests were conducted before and after aging to verify the possible changes of the treated wood and the consolidating resistance. The compound 1:2 of Butvar B98 and sandarac in 5% ethanol was found to be more effective, providing a suitable compound compared to the other consolidants tested.

Keywords: Zelkova carpinifolia, consolidation, synthetic resin, penetration depth, hardness

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Authors: Hyun-Sook Lee, Hongjae Moon, Hwaebong Jung, Sumin Kim, Wooyoung Lee

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Low-temperature phase (LTP) of MnBi has attracted much attention because it has a larger coercivity than that of Nd-Fe-B at high temperature, which gives high potential as a permanent magnet material that can be used at such high temperature. We present variation in magnetic properties of MnBi films by controlling the numbers of Bi/Mn bilayer. The thin films of LTP-MnBi were fabricated onto glass substrates by UHV sputtering, followed by in-situ annealing process at an optimized condition of 350 °C and 1.5 hours. The composition ratio of Bi/Mn was adjusted by varying the thickness of Bi and Mn layers. The highest value of (BH)max ~ 8.6 MGOe at room temperature was obtained in one Bi/Mn bilayer with 34 nm Bi and 16 nm Mn. To investigate the effect of Bi/Mn multilayers on the magnetic properties, we increased the numbers of Bi/Mn bilayer up to five at which the total film thicknesses of Bi and Mn were fixed with 34 nm and 16 nm. The increase of coercivity was observed up to three layers from 4.8 kOe to 15.3 kOe and then suppression was appeared. A reversed behavior was exhibited in the magnetization. We found that these were closely related to a microstructural change of LTP-MnBi and a reduction of growth rate of LTP-MnBi by analyzing XRD and TEM results. We will discuss how the multilayered MnBi affects the magnetic properties in details.

Keywords: coercivity, MnBi, multilayer film, permanent magnet

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Authors: Jiří Kubásek, Peter Minárik, Klára Hosová, Stanislav Šašek, Jozef Veselý, Jitka Stráská, Drahomír Dvorský, Dalibor Vojtěch, Miloš Janeček

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Mg-2Y-2Gd-1Ca and Mg-4Y-4Gd-2Ca alloys were processed by extrusion or equal channel angular pressing (ECAP) to analyse the effect of the microstructure on ignition temperature, mechanical properties and corrosion resistance. The alloys are characterized by good mechanical properties and exceptionally high ignition temperature, which is a critical safety measure. The effect of extrusion and ECAP on the microstructure, mechanical properties and ignition temperature was studied. The obtained results indicated a substantial effect of the processing conditions on the average grain size, the recrystallized fraction and texture formation. Both alloys featured a high strength, depending on the composition and processing condition, and a high ignition temperature of ≈1100 °C (Mg-4Y-4Gd-2Ca) and ≈950 °C (Mg-2Y-2Gd-1Ca), which was attributed to the synergic effect of Y, Gd and Ca oxides, with the dominant effect of Y₂O₃. The achieved combination of enhanced mechanical properties and the ignition temperature makes these alloys a prominent candidate for aircraft applications.

Keywords: magnesium alloys, enhanced ignition temperature, mechanical properties, ECAP

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Authors: Edgar Santoyo, Daniel Perez-Zarate, Agustin Acevedo, Lorena Diaz-Gonzalez, Mirna Guevara

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Four new gas geothermometers have been derived from a multivariate geo chemometric analysis of a geothermal fluid chemistry database, two of which use the natural logarithm of CO₂ and H2S concentrations (mmol/mol), respectively, and the other two use the natural logarithm of the H₂S/H₂ and CO₂/H₂ ratios. As a strict compilation criterion, the database was created with gas-phase composition of fluids and bottomhole temperatures (BHTM) measured in producing wells. The calibration of the geothermometers was based on the geochemical relationship existing between the gas-phase composition of well discharges and the equilibrium temperatures measured at bottomhole conditions. Multivariate statistical analysis together with the use of artificial neural networks (ANN) was successfully applied for correlating the gas-phase compositions and the BHTM. The predicted or simulated bottomhole temperatures (BHTANN), defined as output neurons or simulation targets, were statistically compared with measured temperatures (BHTM). The coefficients of the new geothermometers were obtained from an optimized self-adjusting training algorithm applied to approximately 2,080 ANN architectures with 15,000 simulation iterations each one. The self-adjusting training algorithm used the well-known Levenberg-Marquardt model, which was used to calculate: (i) the number of neurons of the hidden layer; (ii) the training factor and the training patterns of the ANN; (iii) the linear correlation coefficient, R; (iv) the synaptic weighting coefficients; and (v) the statistical parameter, Root Mean Squared Error (RMSE) to evaluate the prediction performance between the BHTM and the simulated BHTANN. The prediction performance of the new gas geothermometers together with those predictions inferred from sixteen well-known gas geothermometers (previously developed) was statistically evaluated by using an external database for avoiding a bias problem. Statistical evaluation was performed through the analysis of the lowest RMSE values computed among the predictions of all the gas geothermometers. The new gas geothermometers developed in this work have been successfully used for predicting subsurface temperatures in high-temperature geothermal systems of Mexico (e.g., Los Azufres, Mich., Los Humeros, Pue., and Cerro Prieto, B.C.) as well as in a blind geothermal system (known as Acoculco, Puebla). The last results of the gas geothermometers (inferred from gas-phase compositions of soil-gas bubble emissions) compare well with the temperature measured in two wells of the blind geothermal system of Acoculco, Puebla (México). Details of this new development are outlined in the present research work. Acknowledgements: The authors acknowledge the funding received from CeMIE-Geo P09 project (SENER-CONACyT).

Keywords: artificial intelligence, gas geochemistry, geochemometrics, geothermal energy

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Authors: Saad Saeed Althiabi

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This paper discusses the corporate positioning and how it became popular as a way to systematize production because of the unique manner in which incorporation legalized organizers to secure financial capital through locking it in. The power to lock in capital comes from the fact that a corporate exists as a separate legal entity, whose survival and governance are separated from any of its participants. The law essentially creates a different legal person when a corporation is created. Although this idea has been played down in the legal learning of the last decades in favor of the view that a corporation is purely something through which natural persons interrelate, recent legal research has begun to reassess the importance of entity status. Entity status, under the law and the related separation of governance from input of financial capital through the configuration of a corporation, sanctioned corporate participants to do somewhat more than connect in a series of business transactions.

Keywords: corporate law, entity status, locking in capital, financial capital

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Authors: Wan Noorul Hafilah Binti Wan Ariffin

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Dam safety management is the crucial infrastructure as dam failure has a catastrophic effect on the community. Dam safety management is the effective framework of key actions and activities for the dam owner to manage the safety of the dam for its entire life cycle. However, maintaining dam safety is a challenging task as there are changes in current dam states. These changes introduce new risks to the dam's safety, which had not been considered when the dam was designed. A new framework has to be developed to adapt to the changes in the dam risk and make the dams resilient. This study proposes a risk-based decision-making adaptation framework for dam safety management. The research focuses on climate change's impact on hydrological situations as it causes floods and damages the dam structure. The risk analysis framework is adopted to improve the dam management strategies. The proposed study encompasses four phases. To start with, measuring the effect by assessing the impact of climate change on embankment dam, the second phase is to analyze the potential embankment dam failures. The third is analyzing the different components of risks related to the dam and, finally, developing a robust decision-making framework.

Keywords: climate change, embankment dam, failure, risk-informed decision making

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Authors: Mohammad F. Fauzi, Nurul H. Shahba M. Shahrun, Nurul W. Hamzah, Mohd Noah A. Rahman, Afzaal H. Seyal

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In this paper, we proposed a simulation system using Wireless Sensor Network (WSN) that will be distributed around the forest for early forest fire detection and to locate the areas affected. In Brunei Darussalam, approximately 78% of the nation is covered by forest. Since the forest is Brunei’s most precious natural assets, it is very important to protect and conserve our forest. The hot climate in Brunei Darussalam can lead to forest fires which can be a fatal threat to the preservation of our forest. The process consists of getting data from the sensors, analyzing the data and producing an alert. The key factors that we are going to analyze are the surrounding temperature, wind speed and wind direction, humidity of the air and soil.

Keywords: forest fire monitor, humidity, wind direction, wireless sensor network

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Authors: Ratchaneewan Salao, Steven W. Edwards, Kiatichai Faksri, Kanin Salao

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Background: A two-dose regimen of COVID-19 vaccination (inactivated whole virion SARS-CoV-2 and adenoviral vector) has been widely used. Side effects are very low, but several adverse effects have been reported. Methods: A 40-year-old female patient, with a previous history of thyroid goitre, developed severe neck pain, headache, nausea and fatigue 7-days after receiving second vaccination with Vaxzevria® (Oxford-AstraZeneca). Clinical and laboratory findings, including thyroid function tests and ultrasound of thyroid glands, were performed. Results: Her left thyroid gland was multinodular enlarged, and severely tender on palpation. She had difficulty in swallowing and had tachycardia but no signs of hyperthyroidism. Laboratory results supported a diagnosis of subacute thyroiditis. She was prescribed NSAID (Ibuprofen 400 mg) and dexamethasone for 3-days and her symptoms resolved. Conclusions: Although this is an extremely rare event, physicians may encounter more cases of this condition due to the extensive vaccination program using this combination of vaccines.

Keywords: SARS-CoV-2, adenoviral vector vaccines, vaccination, subacute thyroiditis

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Authors: Adeyemi, Samuel Olusegun

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Biometrics and dietary habit of Citharinus citharus in the lower Niger River area of kogi state were studied between October and December, 2010. A total of 120 fish sampled were used for the study. The total length, standard length and weight were taken for each fish sample for the estimations of length-weight relationship using the formula W = aLb and transformed to Log W = Log a + b Log L. Stomach contents were analyzed by frequency of occurrence method. The standard length of males, females and combined sexes ranged between 6.8 - 16.5, 7.3 – 14.3 cm, 6.8 – 74.2 (cm) respectively, with b – values of 3.0963, 3.174 and 3.1382. The condition factor ranged from 2.04 – 2.80, 1.88 – 2.86 and 1.88 – 2.86 respectively. The food and feeding habits shows that the fish feeds mainly sand grain (25.83%), mud (24.16%), plant parts (12.50%), insect part (2.50%), algae (12.50%) and unidentified items (5.00%). C. citharus in the lower Niger area of kogi state could be termed to an omnivore. River Niger could be said to be suitable for growth and survival of the fish species C. citharus.

Keywords: length-weight, sexes, stomach content, feeding habits, plant materials

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Authors: Eleni Panagiotarakou

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This paper argues that humans have a collective moral responsibility to help wild animals during the Anthropocene era. Seen from the perspective of deontic logic, this moral responsibility did not exist in the Holocene era (ca. 11,700 BC-1945 AD) on account of humanity’s limited impact on the natural environment. By contrast in the Anthropocene, human activities are causing significant disturbances to planetary ecosystems and by inference to wildlife communities. Under these circumstances controversial and deeply regrettable interventional methods such as Managed Relocations (MR) and synthetic biology should be expanded and become policy measures despite their known and unknown risks. The main rationale for the above stems from the fact that traditional management strategies are simply insufficient in the Anthropocene. If the same anthropogenic activities continue unabated they risk triggering a sixth mass species extinction.

Keywords: anthropocene, humanitarian interventions, managed relocations, species extinctions, synthetic biology

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Authors: Zaid Jamal Saeed Almahmoud

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Smart grid is emerging as the future power grid, with smart techniques to optimize power consumption and electricity generation. Minimizing peak power consumption under a fixed delay requirement is a significant problem in the smart grid.For this problem, all appliances must be scheduled within a given finite time duration. We consider the problem of minimizing the peak demand under appliances constraints by scheduling power jobs with uniform release dates and deadlines. As the problem is known to be NP-hard, we analyze the performance of a version of the natural greedy heuristic for solving this problem. Our theoretical analysis and experimental results show that the proposed heuristic outperforms existing methods by providing a better approximation to the optimal solution.

Keywords: peak demand scheduling, approximation algorithms, smart grid, heuristics

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Authors: Isabelle Barrett

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Natural watercourses provide a range of vital ecosystem services, notably freshwater provision. They also offer highly heterogeneous habitat which supports an extreme diversity of aquatic life. Exploitation of rivers, changing land use and flood prevention measures have led to habitat degradation and subsequent biodiversity loss; indeed, freshwater species currently face a disproportionate rate of extinction compared to their terrestrial and marine counterparts. Large woody debris (LWD) encompasses the trees, large branches and logs which fall into watercourses, and is responsible for important habitat characteristics. Historically, natural LWD has been removed from streams under the assumption that it is not aesthetically pleasing and is thus ecologically unfavourable, despite extensive evidence contradicting this. Restoration efforts aim to replace lost LWD in order to reinstate habitat heterogeneity. This paper aims to assess the current state of such restoration schemes for improving fluvial ecological health in the UK. A detailed review of the scientific literature was conducted alongside a meta-analysis of 25 UK-based projects involving LWD restoration. Projects were chosen for which sufficient information was attainable for analysis, covering a broad range of budgets and scales. The most effective strategies for river restoration encompass ecological success, stakeholder engagement and scientific advancement, however few projects surveyed showed sensitivity to all three; for example, only 32% of projects stated biological aims. Focus tended to be on stakeholder engagement and public approval, since this is often a key funding driver. Consequently, there is a tendency to focus on the aesthetic outcomes of a project, however physical habitat restoration does not necessarily lead to direct biodiversity increases. This highlights the significance of rivers as highly heterogeneous environments with multiple interlinked processes, and emphasises a need for a stronger scientific presence in project planning. Poor scientific rigour means monitoring is often lacking, with varying, if any, definitions of success which are rarely pre-determined. A tendency to overlook negative or neutral results was apparent, with unjustified focus often put on qualitative results. The temporal scale of monitoring is typically inadequate to facilitate scientific conclusions, with only 20% of projects surveyed reporting any pre-restoration monitoring. Furthermore, monitoring is often limited to a few variables, with biotic monitoring often fish-focussed. Due to their longer life cycles and dispersal capability, fish are usually poor indicators of environmental change, making it difficult to attribute any changes in ecological health to restoration efforts. Although the potential impact of LWD restoration may be positive, this method of restoration could simply be making short-term, small-scale improvements; without addressing the underlying symptoms of degradation, for example water quality, the issue cannot be fully resolved. Promotion of standardised monitoring for LWD projects could help establish a deeper understanding of the ecology surrounding the practice, supporting movement towards adaptive management in which scientific evidence feeds back to practitioners, enabling the design of more efficient projects with greater ecological success. By highlighting LWD, this study hopes to address the difficulties faced within river management, and emphasise the need for a more holistic international and inter-institutional approach to tackling problems associated with degradation.

Keywords: biological monitoring, ecological health, large woody debris, river management, river restoration

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Authors: Mmatladi D. Mnguni, Mustapha Mohammed, George Y. Mahama, Alhassan L. Abdulai, Felix D. Dakora

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Industrial-based nitrogen (N) fertilizers are justifiably credited for the current state of food production across the globe, but their continued use is not sustainable and has an adverse effect on the environment. The search for greener and sustainable technologies has led to an increase in exploiting biological systems such as legumes and organic amendments for plant growth promotion in cropping systems. Although the benefits of legume rotation with cereal crops have been documented, the full benefits of soybean-sorghum rotation systems have not been properly evaluated in Africa. This study explored the benefits of soybean-sorghum rotation through assessing N₂ fixation and water-use efficiency of soybean in rotation with sorghum with and without organic and inorganic amendments. The field trials were conducted from 2017 to 2020. Sorghum was grown on plots previously cultivated to soybean and vice versa. The succeeding sorghum crop received fertilizer amendments [organic fertilizer (5 tons/ha as poultry litter, OF); inorganic fertilizer (80N-60P-60K) IF; organic + inorganic fertilizer (OF+IF); half organic + inorganic fertilizer (HIF+OF); organic + half inorganic fertilizer (OF+HIF); half organic + half inorganic (HOF+HIF) and control] and was arranged in a randomized complete block design. The soybean crop succeeding fertilized sorghum received a blanket application of triple superphosphate at 26 kg P ha⁻¹. Nitrogen fixation and water-use efficiency were respectively assessed at the flowering stage using the ¹⁵N and ¹³C natural abundance techniques. The results showed that the shoot dry matter of soybean plants supplied with HOF+HIF was much higher (43.20 g plant-1), followed by OF+HIF (36.45 g plant⁻¹), and HOF+IF (33.50 g plant⁻¹). Shoot N concentration ranged from 1.60 to 1.66%, and total N content from 339 to 691 mg N plant⁻¹. The δ¹⁵N values of soybean shoots ranged from -1.17‰ to -0.64‰, with plants growing on plots previously treated to HOF+HIF exhibiting much higher δ¹⁵N values, and hence lower percent N derived from N₂ fixation (%Ndfa). Shoot %Ndfa values varied from 70 to 82%. The high %Ndfa values obtained in this study suggest that the previous year’s organic and inorganic fertilizer amendments to sorghum did not inhibit N₂ fixation in the following soybean crop. The amount of N-fixed by soybean ranged from 106 to 197 kg N ha⁻¹. The treatments showed marked variations in carbon (C) content, with HOF+HIF treatment recording the highest C content. Although water-use efficiency varied from -29.32‰ to -27.85‰, shoot water-use efficiency, C concentration, and C:N ratio were not altered by previous fertilizer application to sorghum. This study provides strong evidence that previous HOF+HIF sorghum residues can enhance N nutrition and water-use efficiency in nodulated soybean.

Keywords: ¹³C and ¹⁵N natural abundance, N-fixed, organic and inorganic fertilizer amendments, shoot %Ndfa

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Authors: Valeria Dilcheva, Svetlozara Petkova, Ivelin Vladov

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Nemathodes of the genus Trichinella are zoonotic parasites with a cosmopolitan distribution. More than 100 species of mammals, birds and reptiles are involved in the natural cycle of this nematode. At present, T. spiralis, T. pseudospiralis, and T. britovi have been found in Bulgaria. The existence of natural wildlife and domestic reservoirs of Trichinella spp. can be a serious threat to human health. Three trichinella isolates caused human trichinella infection outbreaks from three regions of Sofia City Province were used for the research: sample No. 1 - Ratus norvegicus, sample No. 2 – domestic pig (Sus scrofa domestica), sample No. 3 - domestic pig (Sus scrofa domestica). Trichinella larvae of the studied species were isolated via digestive method (pepsin, hydrochloric acid, water) at 37ºC by standard procedure and were determined by gender (male and female) based on their morphological characteristics. As a reference trichinella species were used: T. spiralis, T. pseudospiralis, T. nativa and T. britovi. Single male and female larvae of the three isolates were crossed with single male and female larvae of the reference trichinella species as well as reciprocally. As a result of cross-breeding, offspring of muscular larvae with T. spiralis and T. britovi were obtained, while in experiments with T. pseudospiralis and T. nativa, trichinella larvae were not found in the laboratory mice. The results obtained in the control groups indicate that the trichinella larvae used from the isolates and the four trichinella species are infective. Also, the infective ability of the F1 offspring from the successful cross-breeding between isolates and reference species was investigated. Through the data obtained in the experiment was found that isolates No. 1 and No. 2 belong to the species T. spiralis, and isolate No. 3 belongs to the species T. britovi. The results were confirmed by PCR and real-time PCR analysis. Thus the presence and circulation of the species T. spiralis and T. britovi in Bulgaria was confirmed. Probably the rodents (rats) are involved in the distribution of T. spiralis in urban environment. The species T. britovi found in a domestic pig speaks of some contact with wild animals for which T. britovi is characteristic. The probable reason is that a large number of farmers in Bulgaria practice the free-range breeding of domestic pigs. Part of the farmers also used as food for domestic pigs waste products from the game (foxes, jackals, bears, wolves) and probably thus the infection was obtained. The distribution range of trichinella species in Bulgaria is not strictly outlined. It is believed that T. spiralis is most common in domestic animals and T. britovi and T. pseudospiralis are characteristic of wildlife. To answer the question whether wild and synanthropic animals are infected with the same or different trichinella species, which species predominate in nature and what their distribution among different hosts is, further research is required.

Keywords: cross-breeding, Sofia, trichinellosis, Trichinella britovi, Trichinella spiralis

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Authors: K. H. Yang, T. C. Yeh, P. S. Lu, F. C. Yang, T. Y. Wu, W. J. Sung

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In this study, a series of full-scale hot smoke tests has been conducted to validate the performances of the smoke management system in the WWY center for arts before grand opening. Totaled 19 scenarios has been established and experimented with fire sizes ranging from 2 MW to 10 MW. The measured ASET data provided by the smoke management system experimentation were compared with the computer-simulated RSET values for egress during the design phase. The experimental result indicated that this system could successfully provide a safety margin of 200% and ensure a safe evacuation in case of fire in the WWY project, including worst-cases and fail-safe scenarios. The methodology developed and results obtained in this project can provide a useful reference for future applications, such as for the large-scale indoor sports dome and arena, stadium, shopping malls, airport terminals, and stations or tunnels for railway and subway systems.

Keywords: building hot smoke tests, performance-based smoke management system designs, full-scale experimental validation, tenable condition criteria

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Authors: Ibnorachid Zakaria, El Bikri Khalid, Benamar Rhali, Farah Abdoun

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The aim of the present work is to study the linear free symmetric vibration of three-layer sandwich beam using the energy method. The zigzag model is used to describe the displacement field. The theoretical model is based on the top and bottom layers behave like Euler-Bernoulli beams while the core layer like a Timoshenko beam. Based on Hamilton’s principle, the governing equation of motion sandwich beam is obtained in order to calculate the linear frequency parameters for a clamped-clamped and simple supported-simple-supported beams. The effects of material properties and geometric parameters on the natural frequencies are also investigated.

Keywords: linear vibration, sandwich, shear deformation, Timoshenko zig-zag model

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Authors: Javier Fernandez, Mayte Medina, Rafael Fernandez de Canete, Nuria Alcain, Juan Carlos Ramos-Diaz

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At present, the experimentation of anesthetic drugs on patients requires a regulation protocol, and the response of each patient to several doses of entry drug must be well known. Therefore, the development of pharmacological dose control systems is a promising field of research in anesthesiology. In this paper, it has been developed a non-linear compartmental the pharmacokinetic-pharmacodynamical model which describes the anesthesia depth effect in a sufficiently reliable way over a set of patients with the depth effect quantified by the Bi-Spectral Index. Afterwards, an Artificial Neural Network (ANN) predictive controller has been designed based on the depth of anesthesia model so as to keep the patient in the optimum condition while he undergoes surgical treatment. For the purpose of quantifying the efficiency of the neural predictive controller, a classical proportional-integral-derivative controller has also been developed to compare both strategies. Results show the superior performance of predictive neural controller during BiSpectral Index reference tracking.

Keywords: anesthesia, bi-spectral index, neural network control, pharmacokinetic-pharmacodynamical model

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Authors: Saeb Ahmadi, Mohsen Vafaie Sefti, Mohammad Mahdi Shadman, Ebrahim Tangestani

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Carbon nanotube has shown great potential for the removal of various inorganic and organic components due to properties such as large surface area and high adsorption capacity. Central composite design is widely used method for determining optimal conditions. Also due to the economic reasons and wide application, the rare earth elements are important components. The analyses of cerium (Ce(III)) adsorption as one of the Rare Earth Elements (REEs) adsorption on Multiwall Carbon Nanotubes (MWCNTs) have been studied. The optimization process was performed using Response Surface Methodology (RSM). The optimum amount conditions were pH of 4.5, initial Ce (III) concentration of 90 mg/l and MWCNTs dosage of 80 mg. Under this condition, the optimum adsorption percentage of Ce (III) was obtained about 96%. Next, at the obtained optimum conditions the kinetic and isotherm studied and result showed the pseudo-second order and Langmuir isotherm are more fitted with experimental data than other models.

Keywords: cerium, rare earth element, MWCNTs, adsorption, optimization

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Authors: Lydia Novozhilova, Vladimir Urazhdin

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An optimization problem for reinforced thin-walled vessels under uniform external pressure is considered. The conventional approaches to optimization generally start with pre-defined geometric parameters of the vessels, and then employ analytic or numeric calculations and/or experimental testing to verify functionality, such as stability under the projected conditions. The proposed approach consists of two steps. First, the feasibility domain will be identified in the multidimensional parameter space. Every point in the feasibility domain defines a design satisfying both geometric and functional constraints. Second, an objective function defined in this domain is formulated and optimized. The broader applicability of the suggested methodology is maximized by implementing the Support Vector Machines (SVM) classification algorithm of machine learning for identification of the feasible design region. Training data for SVM classifier is obtained using the Simulation package of SOLIDWORKS®. Based on the data, the SVM algorithm produces a curvilinear boundary separating admissible and not admissible sets of design parameters with maximal margins. Then optimization of the vessel parameters in the feasibility domain is performed using the standard algorithms for the constrained optimization. As an example, optimization of a ring-stiffened closed cylindrical thin-walled vessel with semi-spherical caps under high external pressure is implemented. As a functional constraint, von Mises stress criterion is used but any other stability constraint admitting mathematical formulation can be incorporated into the proposed approach. Suggested methodology has a good potential for reducing design time for finding optimal parameters of thin-walled vessels under uniform external pressure.

Keywords: design parameters, feasibility domain, von Mises stress criterion, Support Vector Machine (SVM) classifier

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Authors: Karla Peitl Miller, Leomar Bravin Porto, Kaitto Correa Fraga, Nataniele Eler Mendes

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This paper presents the evaluation and study of a real reinforced concrete structure of a fertilizer storage building, constructed on a Vale’s Port at Brazil, which has been recently under refurbishment. Data that will be shared and commented aim to show how wrong choices in project concepts allied to a very high aggressive environment lead to a fast track degradation, incurring on a hazardous condition associated with huge and expensive treatment for repair and guarantee of minimum performance conditions and service life. It will be also shown and discussed all the covered steps since pathological manifestations first signs were observed until the complete revitalization and reparation planning would be drawn. The conclusions of the work easily explicit the importance of professional technical qualification, the importance of minimum requirements for design and structural reforms, and mainly, the importance of good inspection and diagnostic engineering continuous work.

Keywords: durability, reinforced concrete repair, structural inspection, diagnostic engineering

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Authors: Mostafa M. Makrahy, Nouby M. Ghazaly, G. T. Abd el-Jaber

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This paper presents the experimental study of vibration generated by friction materials of an automotive disc brake system using brake test rig. Effects of silica sand particles which are available on the road surface as an environmental condition with a size varied from 150 μm to 600 μm are evaluated. Also, the vibration of the brake disc is examined against the friction material in humidity environment conditions under variable rotational speed. The experimental results showed that the silica sand particles have significant contribution on the value of vibration amplitude which enhances with increasing the size of silica sand particles at different speed conditions. Also, it is noticed that the friction material is sensitive to humidity and the vibration magnitude increases under wet testing conditions. Moreover, it can be reported that with increasing the applied pressure and rotational speed of the braking system, the vibration amplitudes decrease for all cases.

Keywords: disc brake vibration, friction-induced vibration, silica sand particles, brake operational and environmental conditions

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Authors: Abdulah Hamads Alatiah

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The green architecture represents the essence of the sustainability process and the fundamental rule in the desert areas' reconstruction seeking to maintain the environmental balance. This study is based on the analytical descriptive approach, to extract the objectives of green architecture in the desert areas, and reveal the most important principles that contribute to highlight its economic, social, and environmental importance, in addition to standing on the most important technical standards that can be relied upon to deal with its environmental problems. The green architecture aims: making use of the alternative energy, reducing the conventional energy consumption, addressing its negative effects, adapting to the climate, innovation in design, providing the individuals' welfare and rationalizing the use of the available resources to maintain its environmental sustainability.

Keywords: green architecture, the warm-dry climate, natural lighting, environmental quality, renewable energy, weather changes

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Authors: Michela Quadrini

Abstract:

Chord diagrams occur in mathematics, from the study of RNA to knot theory. They are widely used in theory of knots and links for studying the finite type invariants, whereas in molecular biology one important motivation to study chord diagrams is to deal with the problem of RNA structure prediction. An RNA molecule is a linear polymer, referred to as the backbone, that consists of four types of nucleotides. Each nucleotide is represented by a point, whereas each chord of the diagram stands for one interaction for Watson-Crick base pairs between two nonconsecutive nucleotides. A chord diagram is an oriented circle with a set of n pairs of distinct points, considered up to orientation preserving diffeomorphisms of the circle. A linear chord diagram (LCD) is a special kind of graph obtained cutting the oriented circle of a chord diagram. It consists of a line segment, called its backbone, to which are attached a number of chords with distinct endpoints. There is a natural fattening on any linear chord diagram; the backbone lies on the real axis, while all the chords are in the upper half-plane. Each linear chord diagram has a natural genus of its associated surface. To each chord diagram and linear chord diagram, it is possible to associate the intersection graph. It consists of a graph whose vertices correspond to the chords of the diagram, whereas the chord intersections are represented by a connection between the vertices. Such intersection graph carries a lot of information about the diagram. Our goal is to define an LCD equivalence class in terms of identity of intersection graphs, from which many chord diagram invariants depend. For studying these invariants, we introduce a new representation of Linear Chord Diagrams based on a set of appropriate topological operators that permits to model LCD in terms of the relations among chords. Such set is composed of: crossing, nesting, and concatenations. The crossing operator is able to generate the whole space of linear chord diagrams, and a multiple context free grammar able to uniquely generate each LDC starting from a linear chord diagram adding a chord for each production of the grammar is defined. In other words, it allows to associate a unique algebraic term to each linear chord diagram, while the remaining operators allow to rewrite the term throughout a set of appropriate rewriting rules. Such rules define an LCD equivalence class in terms of the identity of intersection graphs. Starting from a modelled RNA molecule and the linear chord, some authors proposed a topological classification and folding. Our LCD equivalence class could contribute to the RNA folding problem leading to the definition of an algorithm that calculates the free energy of the molecule more accurately respect to the existing ones. Such LCD equivalence class could be useful to obtain a more accurate estimate of link between the crossing number and the topological genus and to study the relation among other invariants.

Keywords: chord diagrams, linear chord diagram, equivalence class, topological language

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Authors: Maryam Mehrabpour

Abstract:

The sports industry has recognized its impact on the natural environment and has taken steps to address relevant environmental issues. Two key initiatives have emerged: reducing the ecological footprint of sports activities and utilizing sports as a platform to raise environmental awareness. This article provides an overview of the scholarly research conducted on environmental sustainability in sports. It highlights various environmental programs implemented by sports organizations worldwide and examines the current state of environmental efforts in the field. The research utilized semi-structured interviews, website analysis, and published documents as data sources, and qualitative analysis methods were employed to identify themes representing the current status of environmental efforts in sports.

Keywords: environmental sustainability, sport industry, ecological footprint, environmental awareness, environmental programs

Procedia PDF Downloads 72

Authors: Viney Dixit, Rohit R. Shahi, Ashish Bhatnagar, P. Jain, T. P. Yadav, O. N. Srivastava

Abstract:

Carbons are being widely investigated as hydrogen storage material owing to their light weight, fast hydrogen absorption kinetics and low cost. However, these materials suffer from low hydrogen storage capacity at room temperature. The aim of the present study is to synthesize carbon based material which shows moderate hydrogen storage at room temperature. For this purpose, hydrogenation characteristics of natural precursor coconut kernel is studied in this work. The hydrogen storage measurement reveals that the as-synthesized materials have good hydrogen adsorption and desorption capacity with fast kinetics. The synthesized material absorbs 8 wt.% of hydrogen at liquid nitrogen temperature and 2.3 wt.% at room temperature. This could be due to the presence of certain elements (KCl, Mg, Ca) which are confirmed by TEM.

Keywords: coconut kernel, carbonization, hydrogenation, KCl, Mg, Ca

Procedia PDF Downloads 406

Authors: Olusola Bamisile, Ferdinard Dika, Mustafa Dagbasi, Serkan Abbasoglu

Abstract:

The aim of this study was to model an air conditioning system that brings about effective cooling and reduce fossil fuel consumption with solar energy as an alternative source of energy. The objective of the study is to design a system with high COP, low usage of electricity and to integrate solar energy into AC systems. A hybrid solar assisted air conditioning system is designed to produce 30kW cooling capacity and R744 (CO₂) is used as a refrigerant. The effect of discharge pressure on the performance of the system is studied. The subcool temperature, evaporating temperature (5°C) and suction gas return temperature (12°C) are kept constant for the four different discharge pressures considered. The cooling gas temperature is set at 25°C, and the discharge pressure includes 80, 85, 90 and 95 bars. Copeland Scroll software is used for the simulation. A pressure-enthalpy graph is also used to deduce each enthalpy point while numerical methods were used in making other calculations. From the result of the study, it is observed that a higher COP is achieved with the use of solar assisted systems. As much as 46% of electricity requirements will be save using solar input at compressor stage.

Keywords: air conditioning, solar energy, performance, energy saving

Procedia PDF Downloads 130

Authors: S. Mat Radzi, N. J. Abd Rahman, H. Mohd Noor, N. Ariffin

Abstract:

Ferulic acid has widespread industrial potential by virtue of its antioxidant properties. However, it is partially soluble in aqueous media, limiting their usefulness in oil-based processes in food, cosmetic, pharmaceutical, and material industry. Therefore, modification of ferulic acid should be made by producing of more lipophilic derivatives. In this study, a preliminary investigation of lipase-catalyzed trans-esterification reaction of ethyl ferulate and olive oil was investigated. The reaction was catalyzed by immobilized lipase from Candida antarctica (Novozym 435), to produce ferulate ester, a sunscreen agent. A statistical approach of Response surface methodology (RSM) was used to evaluate the interactive effects of reaction temperature (40-80°C), reaction time (4-12 hours), and amount of enzyme (0.1-0.5 g). The optimum conditions derived via RSM were reaction temperature 60°C, reaction time 2.34 hours, and amount of enzyme 0.3 g. The actual experimental yield was 59.6% ferulate ester under optimum condition, which compared well to the maximum predicted value of 58.0%.

Keywords: ferulic acid, enzymatic synthesis, esters, RSM

Procedia PDF Downloads 316

Authors: Sukhbir Singh

Abstract:

This paper describes the modeling of novel solar air collector (NSAC) system by using artificial neural network (ANN) model. The objective of the study is to demonstrate the application of the ANN model to predict the performance of the NSAC with acetamide as a phase change material (PCM) storage. Input data set consist of time, solar intensity and ambient temperature wherever as outlet air temperature of NSAC was considered as output. Experiments were conducted between 9.00 and 24.00 h in June and July 2014 underneath the prevailing atmospheric condition of Kurukshetra (city of the India). After that, experimental results were utilized to train the back propagation neural network (BPNN) to predict the outlet air temperature of NSAC. The results of proposed algorithm show that the BPNN is effective tool for the prediction of responses. The BPNN predicted results are 99% in agreement with the experimental results.

Keywords: Evacuated tube solar air collector, Artificial neural network, Phase change material, solar air collector

Procedia PDF Downloads 107